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I'm working with a bunch of tools that each have separate coordinate systems and I'm having some confusion about Blender.

For example, add a Monkey to a scene and then examine the Quad view. You should see something like this:

Money Quad View

Notice the following:

  1. The Top view looks at the object from +z pointing to -z and sees the top of the object
  2. The Front view looks at the object from -y pointing to +y and sees the front of the object
  3. The Right view looks at the object from +x pointing to -x and sees the left of the object

In my mind, either the Right view should be relabeled Left OR the model itself should be rotated 180 degrees about the Z axis and the Front view moved to by pointing in the -y direction from +y. In that case, all of the views would point from + to - along the axis (consistently), and the labels for the views would all correspond to intuition.

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  • $\begingroup$ Right and left are relative, the same argument could be made in favor of the current system. $\endgroup$
    – gandalf3
    Commented Oct 20, 2014 at 20:45
  • $\begingroup$ Can you elaborate? For instance, imagine a model of a human. I have a right hand. If I'm viewing from the Right, should I not be seeing the right hand? Just as I see the top of my head when viewing from the Top? I don't see how Right is relative to an object. $\endgroup$
    – aardvarkk
    Commented Oct 20, 2014 at 20:53
  • $\begingroup$ @aardvarkk No, not in that case. What this means is that you see the model from the Right side, which means you see the left side of the mesh. Just like real life. $\endgroup$ Commented Oct 20, 2014 at 20:57
  • $\begingroup$ @someonewithpc Hmm, I see what you're saying, but I think it's problematic to look at it that way, because calling what we see in the current view "looking at the model from the right side" only makes sense if you use a frame of reference that had the camera initially pointed at the front of the object with its up vector aligned with the world "up". Why do we use some arbitrary, detached frame of reference for only one of the views? Shouldn't it be "top sees top of object", "front sees front of object", "right sees right of object"? $\endgroup$
    – aardvarkk
    Commented Oct 20, 2014 at 21:08
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    $\begingroup$ @someonewithpc Well in fairness, that would only be confusing to those who think opposite to me. Currently, if I adjusted to what I thought was the Right view and then tried to snap to Blender's Right view it does exactly what you say and flips around to the "wrong" side. But all of this frames the problem as if it's just a matter of taste. The fact remains that two of the views (top, right) currently look from + toward -, while the remaining view (front) looks from - to +. It doesn't have to be this way! $\endgroup$
    – aardvarkk
    Commented Oct 20, 2014 at 21:21

1 Answer 1

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What is the right side of a house? Or a bed? Or a keyboard or TV? Does the text in a book go from the left side to the right side, or from the right side to the left side?

Even if there's a clear agreement on what the front of an object is, what is considered the left or right side depends on the type of object, so there's no way to have a convention in Blender that always works. What we consider the left side or right side depends on how we humans typically interact with the object.

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  • $\begingroup$ I would consider that the "right" side of an object is the the side which is on your right when looking from the back towards the front. $\endgroup$
    – gandalf3
    Commented Oct 20, 2014 at 22:37
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    $\begingroup$ So the numpad is on the left side of your keyboard? $\endgroup$
    – brecht
    Commented Oct 20, 2014 at 22:38
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    $\begingroup$ Hm. You got me :) $\endgroup$
    – gandalf3
    Commented Oct 20, 2014 at 22:44
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    $\begingroup$ My confusion stemmed primarily from a lack of appreciation for a global coordinate system. By my logic, when I ask for a "right" view of an object that I've rotated in the world, it should still show me the right side. But then the camera views are all invalidated when you rotate something -- and we don't want that. So it makes sense that Blender has a global coordinate system irrespective of any objects in the world. Once I accepted that in my head, the only remaining issue is why the views don't consistently align with +/- directions of the axes, but that's probably an unfortunate legacy. $\endgroup$
    – aardvarkk
    Commented Oct 21, 2014 at 0:14
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    $\begingroup$ About +/- consistency, there are other factors. With the way it works now, if you look from the front, top or right, the 2D coordinate system of the other axes is consistently oriented. So in these 2D views moving to the right or top is always from - to +. That consistency would be lost by flipping the Y axis. $\endgroup$
    – brecht
    Commented Oct 21, 2014 at 9:21

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